Table Of Contents

Get Waveform Subset (G Dataflow)

Version:
Last Modified: August 28, 2017

Retrieves a subset of a waveform at a specified time or index.

connector_pane_image
datatype_icon

open interval

Boolean that determines whether the waveform subset extracted is an open or closed interval. For example, if t0 = 0, dt = 1, Y = {0, 1, 2}, start/duration format is Relative Time, start samples/time is 0, and duration is 2, an open interval returns {0, 1}. A closed interval returns {0, 1, 2}.

True The extracted waveform subset is an open interval.
False The extracted waveform subset is a closed interval.

This input is available when you wire a waveform or digital waveform to waveform.

Default: True

datatype_icon

start/duration format

Value that determines whether to retrieve the data value of the specified element or at a specified time.

This input is available when you wire a waveform or digital waveform to waveform.

Name Value Description
Samples 0 Returns the data value of the specified element in the waveform data.
Relative Time 1 Returns the data value at a specified time relative to the first point in the waveform. In this mode, the dt of the waveform affects actual start samples/time and actual duration.

Default: Samples

datatype_icon

waveform

Waveform from which you want to retrieve a subset.

This input accepts an array of waveforms or an array of digital waveforms.

This input is available when you wire a waveform or digital waveform data type to digital data. If you wire a digital table to waveform, this input changes to digital data.

datatype_icon

digital data

Set of digital data from which you want to retrieve a subset.

This input is available only when you wire a digital table to waveform. If you wire a waveform or digital waveform to digital data, this input changes to waveform.

datatype_icon

start samples/time

Data element or time value where you want to start acquiring a waveform subset.

This input is available when you wire a waveform or digital waveform data type to digital data. If you wire a digital table to waveform, this input changes to start.

Default: 0

datatype_icon

start

Data element or time value where you want to start acquiring a data subset.

This input is available only when you wire a digital table to waveform. If you wire a waveform or digital waveform to digital data, this input changes to start samples/time.

Default: 0

datatype_icon

duration

Amount of time to retrieve data or the number of elements of data you want to retrieve, depending on the start or duration format you select.

This input is available when you wire a waveform or digital waveform data type to digital data. If you wire a digital table to waveform, this input changes to number of samples.

Default: 1

datatype_icon

number of samples

Number of samples to include in the digital data subset.

This input is available only when you wire a digital table to waveform. If you wire a waveform or digital waveform to digital data, this input changes to duration.

Default: 0

datatype_icon

error in

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Default: No error

datatype_icon

waveform subset

Subset of the provided waveform based on the parameters you specify.

This output is a digital waveform when you wire a digital waveform to waveform.

This output is available when you wire a waveform or digital waveform to waveform. If you wire a digital table to waveform, this output changes to digital data subset.

datatype_icon

digital data subset

Subset of the provided digital data based on the parameters you specify.

This output is available only when you wire a digital table to waveform. If you wire a waveform or digital waveform to digital data, this output changes to waveform subset.

datatype_icon

actual start samples/time

Actual data element when the subset was acquired.

This output is available when you wire a waveform or digital waveform to waveform.

datatype_icon

actual duration

Actual number of elements retrieved or the actual amount of time the data values were acquired.

This output is available when you wire a waveform or digital waveform to waveform.

datatype_icon

error out

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Where This Node Can Run:

Desktop OS: Windows

FPGA: This product does not support FPGA devices

Web Server: Not supported in VIs that run in a web application


Recently Viewed Topics